Introduction:

The global prevalence of morbid obesity is increasing, presenting challenges in cardiac surgery. Morbid obesity (body mass index ≥40 kg/m²) is associated with a high burden of cardiometabolic comorbidities and obesity-specific physiological alterations that increase perioperative risk and complicate surgical, anesthetic, and cardiopulmonary bypass management. As the number of obese patients presenting for cardiac surgery rises, a synthesis of current evidence and perioperative strategies is needed to optimize outcomes in this high-risk population.

Methods:

This narrative review identified relevant literature through targeted searches of PubMed and Google Scholar, supplemented by screening the reference lists of key articles. Search terms included combinations of “cardiac surgery,” “morbid obesity,” “obesity,” “cardiopulmonary bypass,” “anesthesia,” “perfusion,” “postoperative complications,” and “critical care.” Studies were mapped to perioperative domains, including anesthesia and respiratory management, surgical and wound-related considerations, perfusion and cardiopulmonary bypass strategy, intensive care unit (ICU) outcomes, renal complications, atrial fibrillation, bleeding, thromboembolism, and mortality. The evidence base was predominantly observational and review-based, with limited randomized evidence.

Discussion:

Obesity poses multifactorial challenges in cardiovascular surgery by altering cardiac morphology, hemodynamics, and perioperative outcomes. Associated comorbidities such as diabetes, obstructive sleep apnea, and pulmonary hypertension increase operative risk and complicate anesthetic and perfusion management. Obese patients demonstrate altered pharmacokinetics, reduced pulmonary compliance, and heightened inflammation, requiring individualized strategies. Available evidence suggests that lean body mass-informed perfusion, selected off-pump CABG, and early extubation may reduce complications, although high-quality randomized evidence remains limited.

Conclusion:

Cardiac surgery in morbidly obese patients requires a coordinated, physiology-driven perioperative strategy to address obesity-specific anatomical and functional challenges. Tailored anesthetic, perfusion, and surgical approaches, supported by close multidisciplinary collaboration, are central to optimizing outcomes. Further research is needed to refine perioperative protocols, improve risk stratification beyond BMI, and clarify long-term cardiovascular outcomes following surgery in this population.